The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
These and all other extrinsic materials discussed herein are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
A. Background on LED Systems
Solid-state light emitting electronic elements, such as, for example, light emitting diodes (“LEDs”), have been developed that output intense white light. Such solid-state electronic devices emit light as a function of input current. Thus, the output light intensity can be readily varied by moderating or adjusting the supplied current. To maintain a constant light level, LEDs require a constant current supply of power. Various applications of lighting require different levels of light intensity. One approach to generating different light levels is to use different quantity of LEDs. Another approach is to change the level of current supplied to a fixed number of LEDs.
Once in the field, conventional light fixtures cannot adjust maximum output light levels and often supply more light than necessary which uses more power than necessary. Thus, there is a need in the art for improved light fixtures.
B. Background on Light Systems with Occupancy Sensors
A typical lighting control system uses an integrated occupancy sensor for actuating light fixtures without operating a manual switch. Conventionally, lighting contractors are integrating off-the-shelf occupancy sensors with light fixtures from various vendors and either AC line voltage or low-voltage 12-24 VDC power depending on what is available in the light fixture or local wiring system. The prior art involves a separate sensor housing, a power supply stage independent from the lighting fixture, a signal wire to interface with the lighting fixture, and a mechanical connector/fastener to mount the sensor housing to the light fixture.
Typically the vendors that make light fixtures are not the same vendors making occupancy sensors. As such, occupancy sensor vendors manufacture generic occupancy sensors that will work with virtually any light fixture or lighting control system. The electronics in the occupancy sensor is powered independently from the light fixture electronics and do not have the efficiency of combining the power stage of the products. Alternatively, the power input to the occupancy sensor may not even be available in the light fixture, which can affect the manufacturer's decision in selecting how to power their products. Thus, there is a need in the art for improved lighting fixtures.
C. Background on Power Connector Systems
A common application of a disconnect for electrical wiring circuits is in commercial light fixtures often referred to as a “luminaire disconnect”. Such fixtures require an electronic driver to operate. Drivers are typically hard-wired between the power supply and the lighting elements. When a driver or power supply fails it has to be replaced, which can be problematic. Thus, there is a need in the art for improved lighting systems.
D. Background on Power Distribution Systems
LEDs as a source of lighting are now in the mainstream and the technology uses direct current (DC) rather than alternating current (AC) that conventional lamps and bulbs use. LED lighting arrays can be powered directly via direct current (DC) or use alternating current (AC) to direct current (DC) convertors (AC/DC). At low power (less than 50 W) it is difficult to convert AC to DC power in an efficient manner. As the power requirement is reduced so is the efficiency of conversion, which leads to the paradigm that as LEDs become more efficient, the power conversion becomes less efficient. LEDs used in light fixtures typically have a significantly longer life than conventional lamps or bulbs changing the paradigm of failures in lighting fixtures from one of changing lamps/bulbs to a system dealing with failures of power supplies. While the failure rate of lamps and bulbs is in the range of a few years, failures for power supplies are on the order of 5 to 10 years and LEDs can last 20 to 30 years. Thus, there is a need in the art for improved lighting systems.
E. Background on Sealed Lighting Fixtures
A high performance, high efficiency solid state electronic lighting device, having a sealed fixture body for use in environments requiring Ingress Protection (IP) rated (IEC standard 60529) sealed fixtures, generates heat inside the sealed device from the lighting elements thereby causing electronic inefficiencies of powering and controlling the lighting elements, including optional sensors, such as ambient light, occupancy, temperature, etc. The challenge in the art is to reduce the temperature, which is generated in a sealed lighting fixture. Thus, there is a need in the art for improved lighting systems.
F. Background on Enclosures for LED Systems
A common problem in conventional lighting fixtures in the ingress of dust, insects and other contaminants that build up over time and requires disassembly of the light fixture in order to be cleaned. Keeping bugs and dust out of the inside of the optical lens means that light intensity is not diminished, aesthetics of the light are not affected, and maintenance costs are minimized by not having to open up the fixture to remove the material. It is further desirable to have a sealed light compartment whose design can accommodate the removal of heat from the lighting elements by providing a heat sink for the lighting elements. Regardless of the application, it is advantageous that the LED circuitry is housed within some type of protective enclosure. Thus, there is a need in the art for improved lighting systems.
G. Background on Light Fixture Housings
Light fixtures can vary in difficulty in assembly and disassembly, and often require tools or fasteners. The use of tools and fasteners limits the type of materials that are used to produce light fixtures. This can be problematic when softer materials such as aluminum or copper that offer improved heat dissipation as compared to conventional steel housings. Thus, there is still a need in the art for improved lighting fixture systems.